Apparatus for separating sulfuric acid.



PATENTED SEPT. 24, 1907.

F. G. GOTTRBLL. l APPARATUS PoR SBPARATING SULPURIG ACID.

PPLIGATION FILED JNA, 1906.

UNITI-11i STATES PATENT OFFICE! -FREDERIOKGBDNEE oo'rfIRELL, OEBERKELEY, CALIFORNIA, AssIGNOR OE ONE-HALF To HARRY EAST MILLER, OEOAKLAND, CALIFORNIA.

' APPARATUS FQR SEPRATING- SLFURIC ACID.

Specification of Letters Patent.

Patented Sept. 24, 19,075

Applicaiol med January 4, 1906. serial No. 294,524.'

l To all 'whom it may concern:

Be it known that I, FREDERICK GArRDNER COTTRLL, a citizen, ofthe UnitedStates, residing atV Berkeley,

county of Alameda, .State of California, have invented v after fullydescribe.

rial No. 294,523, filed January 4, 1906, and ,which may be briefly andgenerally stated to consist in the separation and collection of thevsulfuric 'acid previously disseminated in the form of f ine liquidparticles through.

indifferent gases. This mixture is formed by hydrating sulfur trioxidmixed with indifferent gases, whereby a fog or mist results, in whichfine particles of sulfuric acid are held in suspension, which saidparticles under the influence.of'centrifugal action, are separated,

collected and discharged.

In an apparatus for this purpose, itis essential to provide asuitableseal for the rotating shell which will present the escape of the gases,while still providing f or the discharge of the collected sulfuric acid.,Such a seal, together with the novel construction of the rotatingshell, constitute my apparatus.

Referring to the accompanying drawings, Figure l is a vertical sectionillustrative of the liquid seals ofthe apparatus; Fig. v2 is a verticalsection of the same.

vReferring to Fig. 1, A is a pipe to deliver the gases with theirsuspended mist or fog tothe shell C, which shell is mounted in suitablebearings D, here shown as in the nature of ball bearings. Theshell hasimparted to ita rotary motion about" its axis, by the application ofsuitable power, indicated by the belt M. B is the escape pipe for thegases. The pipes A and B are nonrotating, being held stationary by anysuitable means.

In'order to provide a gas tight joint or connection' between them andthe rotating shell, lthere is a liquid seal, guarding the connectionagainstthe escape ofthe gases from the shell. This seal is best `formedas folis provided with a footlange a which lies between and is separatedfrom, the ianges c and c. To form` the seal a small quantity of liquidis poured vinto the top of the shell C around the pipe A, which, asshown,

lar wall, represented by w, in the space between the i two flanges c andc and completely enveloping the foot ange a of the pipe A, so that nogas can escape. Any surplus of the liquid will find its way down intothe shell, and be discharged below. The seal at the bottom of the shellis formed by the collected sulfuric acid itself, as shown at w and isprovided forby a bottom flange o2 on the inner surface of the shell C,and ahead flange b on the top of the gas discharge .pipe B, which saidflange overlaps and is separated oni the flange c2 by a slight space, asshown. An annular opening c3 is left between the flange c2 and the pipeB for the discharge ofthe collected sulfuric acid, said discharge beingdelivered into the encircling trough E, and thence through a spout F toits destination.

In using this apparatus, the gaseous mixture with its fog ormistcontaining the'fine particles of sulfuric acid in suspension, is fedd'wn through the pipe A' into the rotating shell 0. In this shell the neparticles of..liquid sulfuric acid are separated by centrifugal actionfrom the gases Land collect upon the walls of the shell and pass down tothe bottom. In the bottom,

assuming the parabolic forni due to centrifugal action, -the liquidsulfuric acid collected there forms the seal w against the escape ofgases, around the pipe B.

The acid continuously discharges through the anl nular opening o3 and isdelivered intol the trough E, and discharged from the spout F. Theliquid seal w maintained at the top by centrifugal action prevents thegas from escaping from the upper end of the apparatus.

In some cases, an inner concentric core, represented -f by S, may beused.` This core is closed'at both ends, and is supported firmly withinthe shell C, concentric with'said shell, and rotating withv it. Thesupports are arranged to liold the shell and core rigidly together, butthey'permit the free passage of-the gases through theannular spacebetween them, with which said space the pipes A and B communicate. Theobject of this arrangement is to maintain asl much as possible of thegas and suspendedmist inside the shell within a region wherehighcentrifugal force is lactive, Which is notV the case near the axis ofrotation. In Fig. 2, the complete apparatus is shown, similar lettersbeingA used where applicable. A `represents the inlet pipe, whichcommunicates through the liquid seal connection w. as before described,with the rotating separating shell. Inthis case, the shell is composedof air outer shell C, I and a series-of concentric, spaced, inercylinders R,

forming a series of annular functionally operative and extensive passageis provided, as is indicated by the arrows, for the iow of the gasesyfrom the central eed to the exterior shell. The outlet tor the gasesis, in this case, at the top, small openings c, being made in the upperplate P at the top of the outermost space of the shell, said openingscommunicating with a chamber c5 above the plate. With a Deck c6 0f thischamber the discharge pipe B communicates by means oi a liquid sealconnection similar to the seal w at the entrance to said shell. Thedischarge of the collected sulfuric acid is obtained through obliquelydirected ducts Q, in the bottom plate O, which opens into thesurrounding trough E, the latter being provided with a spout F. I n thisinstance the shell C is shown as mounted upon a shaft N supported inbearingsDx and having power applied to it by means of a pulley M.

l As the gases pass through, as indicated by the arrows,

the liquid and any solid particles tend to be deposited; by the actionof centrifugal force, on the inner surfaces of the cylinders R and theshell C, that which is de-4 posited on the cylinders R eventuallyreaching the sheu o.

Under steady running conditions, this liquid will assume the usualparabolic curve along the shell C, the layer being thickest at thebottom. When this layer attains a certain thickness, it will flow out atthe bottom through the ducts Q, meanwhile forming a liquid seal w toprevent the escape of gases through,

this same route. When the machine is brought to res-t, the remainder ofthe liquid flows out through the same channels.

It has long been recognized by sulfuric acid manu iacturers that whengases containing white fumev are passed through a centrifugal blower,y avery con siderable quantity of liquid is precipitated out in the casingof the same. This saine principle has beenjap- 'esami plied to freegases of suspended particles, notably i`ri the iron industry. In thesecases, however, the outer containing shell on which the suspended matteris precipitated, remains stationary, and the gas is caused to rotatewithin it, by the rotation of separate moving parts Within. In thepresent apparatus, on the other hand, the outer containing shell isitsel a part of the rotating system. Where the outer shell isstationary, the speedvof rotationcf the gas must decrease as the surfaceof this outer shell is approached and the centrifugal force Will thusfall off in this region; whereas in the above described apparatus, withrotating outer shell, the centrifugal force increases right up to thepoint where the suspended parts are deposited. Furthermore, thisarrangement reduces the effect of eddy currents, which tend to sweepsome of the particles which have been carried part way to the peripheryby centrifugal force, back into the body of the gas once more, and thusgreatly cut down the eiliciency ofthe operation. i v

Having thus described the invention, what l claim as new and desire, tosecure by Letters Patentl isf- In a centrifugal apparatus for theseparation of neugaseous particles from e gaseous body in which tney areheld in suspension, a rotating shell having within it a plurality ofconcentric spaced cylnders #arming a series. of functionally operativeannular channels for separation, a non-rotating pipe leading into saidshell, and a noni'otatlng pipe issuing therefrom, both pipescommunicating with said channels, a liquid seal guarding the ttlng ofeach pipe against the escape of gas from the shelLand means fordischarging the separated non-gaseous particles from said ebannels.

In witness whereof l have hereunto Set my hand.

FREDERICK GARDNER CO'ITRIlLLn Witnesses: .L COMPTON,y

D. B. RICHARDS.

